This thesis examines localities in the vicinity of cities, starting with Ekeby- Almby which is situated near Örebro. In the past twenty years, Ekeby- Almby has experienced vast sociodemographic changes. These lines of development give rise to a number of questions. For example, does the socioeconomic change of Ekeby-Almby reflect a general trend for this kind of locality? What are the perspectives and concepts that characterise the planning of these localities, and what is the significance of these suburban areas for the urban development as a whole? The purpose of this thesis is to examine the peri-urban localities, their role in, and their significance to, the development of cities. The thesis is made up of three empirical parts. Some of the main results are that the peri-urban localities can bedescribed as continuously growing, even during periods of shrinking towns and growing countryside (70s and 80s), and re-urbanisation (90s and 00s). Other results from the study are that layers of peri-urban localities with partially separatesocioeconomic profiles become apparent. Together these localities are, in various ways, part of the city’s socioeconomic differentiation. Finally, the result from the study indicates that the development of localities is shaped by a series of structures, and actors operating in relation to these. The development of the peri-urban localities can, theoretically, be seen as an urban counter- urbanisation, but perhaps primarily as a Swedish periurbia, and thus as an extension of the city, often described as an urban sprawl. This study also discusses the role of the peri-urban locality in the city’s social geography, where it among other things can be described as the ”hidden” space of the segregated city. Another aspect of the peri-urban locality is that it can be seen as a place which is important in an intermunicipal competition in population growth.